Alpha-tocotrienol is a natural antioxidant and it protects glutamate-induced death of neuronal cells (brain cells). It is a member of Vitamin E family with 4 different isomers of trienols (alpha, beta, gamma, and delta) and 4 different isomers of pherols (alpha, beta, gamma, and delta). Alpha-tocotrienol has the following structure:

Tocotrienols occur largely in palm oil extract, rice bran oil, and barley. While synthetic and natural tocopherols are readily available in the market, the supply of natural tocotrienols is limited, and generally comprises a mixture of tocotrienols. Crude palm oil extract which is rich in tocotrienols (800-1500 ppm) offers a potential source of natural tocotrienols. Carotech, located in Malaysia, is an industrial plant able to extract and concentrate tocotrienols from crude palm oil extract. Carotech uses a molecular distillation process (employing ultra-high vacuum and very low temperature) in its production plant. This process (see U.S. Pat. No. 5,157,132) allows Carotech to extract phytonutrients such as the Tocotrienol Complex (TOCOMIN™, a registered trademark of Carotech for extracts and concentrates of palm tree fruits) from the crude palm oil extract. TOCOMIN™-50 typically comprises about 25.32% mixed tocotrienols (7.00% alpha-tocotrienol, 14.42% gamma tocotrienol, 3.30% delta tocotrienol and 0.6% beta tocotrienol), 6.90% alpha-tocopherol and other phytonutrients such as plant squalene, phytosterols, co-enzyme Q10 and mixed carotenoids.
Methods of purification of component of alpha-tocotrienol from palm oil extract have been disclosed in literature, but such methods comprise either separating all the isomers of tocotrienols from the remaining tocopherols or using a complex series of reactions to convert other forms of trienols to the alpha form.
Methods of purification of alpha tocotrienol in small amounts have been disclosed using reverse phase chromatography in conjunction with a C18 adsorbent. Such methods have not proved to be economical for commercial scale production. For examples of such reverse phase chromatographic methods see U.S. Pat. No. 4,122,094; U.S. Pat. No. 5,190,618 and U.S. Pat. No. 5,908,940. More recently, U.S. Pat. No. 8,106,223 discloses methods of the production, enrichment and isolation of pure alpha-totrienol by a combination of functionalization of non-alphatocols by reaction and extraction from source material comprising at least one tocotrienol which is not alpha-tocotrienol.
Simulation of a moving sorbent bed is described in U.S. Pat. No. 2,985,589 (Broughton et al.), which is mentioned above. In accomplishing this simulation, it is necessary to connect a feed stream to a series of beds in sequence, first to bed no. 1, then to bed no. 2, and so forth for numerous beds, the number of beds often being between 12 and 24. These beds may be considered to be portions of a single large bed whose movement is simulated. Each time the feed stream destination is changed, it is also necessary to change the destinations (or origins) of at least three other streams, which may be streams entering the beds, such as the feed stream, or leaving the beds. The moving bed simulation may be imply described as dividing the bed into series of fixed beds and moving the points of introducing and withdrawing liquid streams past the series of fixed beds instead of moving the beds past the introduction and withdrawal points. A rotary valve used in the Broughton process may be described as accomplishing the simultaneous interconnection of two separate groups of conduits.
U.S. Pat. No. 4,412,866 describes an example of the operation of chromatographic simulated moving bed (or sometimes called “SMB”) method to separate the components of a feedstock. A resin bed is divided into a series of discrete vessels, each of which functions as a zone within a circulation loop. A manifold system connects the vessels and directs, in appropriate sequence to (or from) each vessel, each of the four media accommodated by the process. Those media are generally referred to as feed stock, eluent, extract and raffinate, respectively. As applied to a sugar factory, a typical feed stock is a lower purity sucrose solution, the eluent is water, the extract is an aqueous solution of sucrose and the raffinate is an aqueous solution containing non-sucrose, such as salts and high molecular weight compounds. The simulated moving bed disclosed by the '866 patent is of the type sometimes referred to as a “continuous SMB.”
Examples of simulated moving bed processes are disclosed, for instance, in U.S. Pat. No. 6,379,554 (method of displacement chromatography); U.S. Pat. No. 5,102,553 (time variable simulated moving bed process), U.S. Pat. No. 6,093,326 (single train, sequential simulated moving bed process); and U.S. Pat. No. 6,187,204 (same), each of the contents of the entirety of which is incorporated herein by this reference.
Methods are sought for a more efficient method of producing alpha-tocotrienol in pure form from palm oil extract and in a continuous production process with minimum processing steps and at low cost.